Section modulus of Hollow Circular Section having external Dia. (D) and internal Dia. (d) is
1
\(\frac{\pi}{32}\times{(D\;-\;{d^4})}\)
2
\(\frac{\pi}{36}\times\frac{(D^4\;-\;{d^4})}{D}\)
3
\(\frac{\pi}{32}\times\frac{(D^4\;-\;{d^4})}{D}\)
4
\(\frac{\pi}{36}\times{(D\;-\;{d^4})}\)